Thanks for all the input.
@Dangtx - All the power cables were plugged in :P Since the BIOS splash didn't show up either, I don't think it was the drivers.
@Arinoth - Since my mobo doesn't have onboard graphics, would it always default to a discrete one? I'm using both monitor ports so at least one of them would show up. Good call on the multidesktop thing. I remember another setup I had that had that problem.
@JoelPack - That's interesting. I do notice that my monitors take some time to kick in after they enter power saver, but the displays didn't come back at all, even after entering Windows (or at least from what I could hear).

Regardless, upon one of the reboots, when I was trying to replicate the problem, it autostarted a recovery/repair thing so I just went ahead with it. I rebooted several times this morning just to test and it seems to work fine now. It might have been that while installing a program that required a restart, something went wrong. But everything seems to be back in order now.